Intel has just released more details about the new Haswell processors. It sets new benchmarks in terms of energy efficiency. The new C6 and C7 states are able to reduce the CPU power consumption to just 0.05A while previous Ivy Bridge processors draw up to ten times more minimum power.

But the positive progress of the CPU technology is subject to certain restrictions, because only few power supplies will be able to deliver stable voltages at such low loads. End users are therefore groping in the dark with no clues if their own power supply will be compatible with the new energy functions of Intel Haswell CPUs. PSU manufacturers usually do not state the possible minimum load of their products.

Compatibility of Enermax Power Supplies
As one of the technologically leading power supply manufacturers, Enermax makes a step forward and publishes a PSU compatibility list. All current high-end and mid-range models from Enermax are already prepared for the upcoming Intel processors. They are equipped with a DC-to-DC converter which enables the so-called ZERO Load Design. These power supplies will deliver rock-stable voltages even at 0W load. Also the owners of older Enermax power supplies can be relieved: The manufacturer applies the ZERO Load Design already in all high-end power supplies since the Revolution85+ series which has been launched in 2008.

This is just another half-arsed Intel effort to lower power consumption because they can't do the job properly in their CPU/APUs. Intel's approach is at odds with all U.S. and European PSU efficiency standards.

As far as the Seasonic data listed above it does not tell you anything about the minimum 12V rail power under minimum load conditions. This is something that will need to be published (now) by all PSU makers due to Intel's stupidity and non-compliance with world power efficiency standards.

C6 state is nothing new. My rather old Nehalem already has it. Not sure why the brag about it.

Besides, is this really the best way to market it? I mean, they are saying it in a way like you need some super special PSU just to use the Haswell...

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Well, I'm using an older Bronze rated PSU with a Seasonic core and it has quite high minimum load ratings, so I doubt I can get away with C7. Previously with teh VRM on the motherboard, you could shutdown all power to a CPU core, even though the motherboard was still draawing power and turning it into heat. With the VRM controller now on the CPU, the PSU must be able to regulate from 0W.

How did you work that out?? If its 10x more efficient seems like it would be more.

How much does a normal computer cost to run a year? I did see some story on a website that broke it down, I think it was a few hundred a year or something but cant remember exactly. I guess it will only help if your computer is idle a lot, like if you keep it on overnight.

It would be good for temps and noise, the other thing is for mobile battery life. If you can get an extra hour or 2 outta the battery, that's a big deal.

That's the thing with modern power saving devices, individually it might not seem like its worthwhile, but if you have several devices and electronics through the house, all with modern power saving features, it can start to become worthwhile and will save hundreds every year.

Also if you're a business with hundreds/thousands of computers that are on 24/7 it can be worthwhile too.

How did you work that out?? If its 10x more efficient seems like it would be more.

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It could be 100x more efficient, but if we're talking 5W vs .5W there's isn't much to be saved really. By my calculations it should be less than $7.

Let's say your power costs 12c per kW/h, and your spiffy new Haswell system is going to spend all of 365 days in C7 sleep (awesome, I know! buy a new system and make it idle all-year-long, but that's how we roll ):

The new haswell architecture will require a 0.05Amp current over the 12v2 rail when entering c6/c7 power states, much lower than current gen (which only requires 0.5Amps) which is NOT standard even on pro-grade PSUs

It could be 100x more efficient, but if we're talking .5W vs .005W there's isn't much to be saved really. By my calculations it should be much less than $7.

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Yes it's obviously much less than $7, but I was just making a joke with a random low number. I don't think that C6 vs C7 would really matter on an annual scale, even if you would use a 98% efficient PicoPSU.

This new C7 is obviously targeting the mobile segment where every bit and saved power matters. It's just that the guys at Enermax are doing a very clever thing by jumping on this C7 thingy. Props to them for this idea, and they indeed deserve credit if sales will go up because of this campaign.

The new haswell architecture will require a 0.05Amp current over the 12v2 rail when entering c6/c7 power states, much lower than current gen (which only requires 0.5Amps) which is NOT standard even on pro-grade PSUs

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The effective resistance on the 12v rail will be 240 ohms. So you are saying a decent PSU can't deliver 0.05A ? What will it do, drop to 0 volts?

This new C7 is obviously targeting the mobile segment where every bit and saved power matters. It's just that the guys at Enermax are doing a very clever thing by jumping on this C7 thingy. Props to them for this idea, and they indeed deserve credit if sales will go up because of this campaign.

Yes it's obviously much less than $7, but I was just making a joke with a random low number. I don't think that C6 vs C7 would really matter on an annual scale, even if you would use a 98% efficient PicoPSU.

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Actually I re-did things and it seems $7 isn't too far off the mark so +1 for your estimation skills.

Ok fair enough.... but our electricity rate is closer to 20c kw/h so lets say $10 a year....but that's just one part of your PC. If you have a GPU that does something similar, a motherboard, a monitor etc it might be $30 over the year for the computer as a whole. Then you might have 2 or 3 computers in the house so that's $90 a year.

Or you might be upgrading from a Pentium 4 (not the most recent fairly efficient ivy bridge) so it might be double that again.

Then if you have a bunch of other electronics, tvs, hifis, air conditioning, heaters, refrigerator, light bulbs etc all with modern power saving features, all this can add up to hundreds a year.

If you're a business still running 300 Pentium 4's computers it could be hundreds a year.